Evaluations of Biomarker Status Changes between Primary and Recurrent Tumor Tissue Samples in Breast Cancer Patients.

BACKGROUND: Obtaining tumor specimens and re-evaluating targeted markers is recommended, if possible, in breast cancer patients who relapsed after curative treatment. The biomarker status changes in rebiopsied tumors have been demonstrated to have considerable clinical implications. OBJECTIVES: To identify the changes of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) status between the primary and recurrent lesions. MATERIALS AND METHODS: We conducted a study among 67 patients with recurrent breast cancer, recruited from January 2014 to September 2018 in the Vietnam National Cancer Hospital to compare ER, PR, and HER2 status between the primary and recurrent lesions. For each patient, a specimen of their primary tumor and another specimen of recurrent lesions underwent pathological assessment. Immunohistochemistry (IHC) was performed to determine ER, PR, and HER2 status in both specimens. RESULTS: Biomarker status conversion rates (in both directions) between primary and recurrent tumors were 26.9% for ER, 38.8% for PR, and 22.4% for HER2. Overall, IHC subtypes (hormone receptor positive, HER2 amplified, and triple-negative) changed in 25 out of 67 (37.3%) cases. Conversion rates were not statistically significantly different between patients with different recurrent sites and times of recurrence. Eight out of 13 initially triple-negative patients (61.5%) had a change to positive status of either ER, PR, or HER2. CONCLUSION: A substantial discordance in ER, PR, and HER2 status were observed between primary breast cancer tissues and recurrent lesions. Rebiopsy could bring new therapeutic opportunities in the management of patients with recurrent breast cancer.

Association of a single nucleotide polymorphism at 6q25.1,rs2046210, with endometrial cancer risk among Chinese women / 癌症

A recent genome-wide association study identified a new susceptibility locus for breast cancer, rs2046210, which is a single nucleotide polymorphism (SNP) located upstream of the estrogen receptor α(ESR1) gene on chromosome 6q25.1. Given that endometrial cancer shares many risk factors with breast cancer and both are related to estrogen exposure and that rs2046210 is in close proximity to the ESR1 gene, we evaluated the association of SNP rs2046210 with endometrial cancer risk among 953 cases and 947 controls in a population-based, case-control study conducted in Shanghai, China. Logistic regression models were used to derive odds ratios (ORs) and 95% confidence intervals (95% CIs) after adjusting for potential confounders. We found that the A allele of rs2046210, linked to an increased risk of breast cancer, was associated with increased but not statistically significant risk of endometrial cancer (OR = 1.16, 95% CI = 0.96-1.41 for the GA and AA genotypes compared with the GG genotype); the association was stronger among post-menopausal women (OR = 1.28, 95% CI = 1.00-1.65). The association tended to be stronger among women with higher or longer estrogen exposure than among women with relatively lower or shorter exposure to estrogen. Our study suggests that rs2046210 may play a role in the etiology of endometrial cancer. Additional studies are needed to confirm our findings.